Piston ring



Feb. 24. 19,25. 1,527,834

J. W. BULLIS v PISTON RING Filed Aug. 1923 Hlllllllfink v INVENTOR.

JFHTIES. LLI. EIULL IS BY ATTORNEY 1 Patented Feb. 24, 1925-.

UNITED STATES PATE T OFFICE.

muss w. BULLIS, or sanra Rosa, oanrronavu.

PISTON BIN Application filed August .1, 1923. Serial No. 655,101.

. useful Improvements in Piston Rings, of

which the following is a specification.

This invention ielates to new and useful 7 improvements in piston ringsand has par- 10 'ticular reference to a piston ring which willautomatically expand due to pressure within a the cylinder.

Another object is to provide a ring of this character which will alsoact as an efficient oil seal.

A still further object is to provide a ring which ischeap to manufactureand simple to install, also one which may be used in the average pistonwithout altering the construction ofthe same.

Dther objects and advantages will be ap- Parent during the course of thefollowing description.

In the accompanying drawings formin 2 a part of this specification, andin which like numerals are employed to designate like parts throughoutthe same, f

Figure 1 is a fragmentary.v detail view of a section of a piston andcylinder wall showing my ring in use therewith.

Figure 2 is a fragmentary detail view showing the position of the end ofthe outer rings in respect to the inner ring,

Figure 3 is a perspective view of my ring. Applicant is aware of theiactthat double rings have been employed. These rings, however, have beenplain rings with the result that they were little better than "theaverage single ring. I have, therefore 40 soughtto provide a ring havinga feathered edge which will intimately, contact the wall of thecylinder.

In the accompanyingv drawings wherein for the purpose of illustration isshown a preferred embodiment of my invention, the numeral 5 designatesthecylindei' wallythe numeral 6 the piston movingwithin the cylinder.the numeral 7 the usual wrist pin and 8 the usual ring groove. 5 Theconstruction thus far described is identical with that common to allinternal combustion engines. Within the ring tioned my ring whichconsists of two parts,

W. BULLIS,

groove 8, I have posian inner ring 9 and an outer ring 11. It will benoted that the inner ring has a base 12, immediately above which isformed a groove 13 and that the upper edge of this ring is chamfered 'asshown at let. The

outer ring 11 is also chamfered as shown at 16, and has a projectingportion 17 adapted tofit within the recess 13 of the ring 9. The ends ofthe inner ring are out in the usual manner while the ends of the outerring are stepped as shown at Figure 1, and a pin 18 is provided whichpin prevents the two parts from rotating with respect to each other. a

It will thus be seen that when the ring s, is employed in the positionshown in Figure 1, the pressure above the piston, will contact the ring11 and will exert pressure against the rings ,9 and 11, as shown bydotted arrows in Figure 1, forcing the rings apart and against thepiston, andmylinder respectively.

Whenthe ring "is revrsed, the chamfered' Y edge 16 will serve to scrapthe oil from the cylinder wall, thereby preventing the same from workingto a point above the cylinder head and thus fouling the sparkplug andvalves. y v

It will thus belseen that I have protided y a very simple structurewhich accomplishes the objects set forth. 1

It is to be understood-that the form of my invention, herewith shown anddescribed is to be taken as a preferred example of the same, and thatvarious changes in the shape, size and arrangement of parts may beresorted to without departing from the spirit of ,the inventionf or thescope of the subjoined claim.

. Having thus described my invention, I claim A piston ringcomprising'a-n inner ring, an outer ring, said inner ring having a rooveformed therein, said outer ring havlmg a base adapted to enter thegroove in said inner. ring, means \for preventing'rotation of saidrings, with respect to each other and each. ofsaid rings having theirupper margins chamfered, for the purpose specified.

In testimony whereof I affix my signa- 105 ture.

JAMES w. BULLIS.

